scholarly journals Preparation and analysis of peptide fragments produced by pepsin hydrolysis of human plasma albumin and their relationship to its structure

1968 ◽  
Vol 109 (1) ◽  
pp. 107-120 ◽  
Author(s):  
G. Franglen ◽  
G. R. E. Swaniker
Keyword(s):  
Human Plasma ◽  
Gel Filtration ◽  
Tripartite Model ◽  
Peptide Fragments ◽  
Plasma Albumin ◽  
Molecular Weights ◽  
Ph Values ◽  
Cystine Content ◽  
Zone Electrophoresis ◽  
Hydrolysis Of

Human plasma albumin was prepared and subjected to proteolysis by pepsin at pH2·45 at 25° for 10min. with albumin/pepsin ratio 3000:1. Five peptide fragments were detected in the proteolysate by means of zone electrophoresis and gel filtration; these were separated and purified. Molecular weights, amino acid composition and disulphide bond content of the purified fragments were determined. The results show that a high proportion of the polypeptide chain of albumin appears to have a low cystine content, and at low pH values the molecule would be expected to have a considerable degree of freedom in its structure in these regions of the chain. A tripartite model for the structure of plasma albumin is proposed.

scholarly journals Purification and Characterization of 2,6-β-d-Fructan 6-Levanbiohydrolase fromStreptomyces exfoliatus F3-2

2000 ◽  
Vol 66 (1) ◽  
pp. 252-256 ◽  
Author(s):  
Katsuichi Saito ◽  
Kazuya Kondo ◽  
Ichiro Kojima ◽  
Atsushi Yokota ◽  
Fusao Tomita
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Extracellular Enzyme ◽  
Molecular Weights ◽  
Sds Page ◽  
Monomeric Structure ◽  
Ph Range ◽  
Hydrolysis Of

ABSTRACT Streptomyces exfoliatus F3-2 produced an extracellular enzyme that converted levan, a β-2,6-linked fructan, into levanbiose. The enzyme was purified 50-fold from culture supernatant to give a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of this enzyme were 54,000 by SDS-PAGE and 60,000 by gel filtration, suggesting the monomeric structure of the enzyme. The isoelectric point of the enzyme was determined to be 4.7. The optimal pH and temperature of the enzyme for levan degradation were pH 5.5 and 60°C, respectively. The enzyme was stable in the pH range 3.5 to 8.0 and also up to 50°C. The enzyme gave levanbiose as a major degradation product from levan in an exo-acting manner. It was also found that this enzyme catalyzed hydrolysis of such fructooligosaccharides as 1-kestose, nystose, and 1-fructosylnystose by liberating fructose. Thus, this enzyme appeared to hydrolyze not only β-2,6-linkage of levan, but also β-2,1-linkage of fructooligosaccharides. From these data, the enzyme from S. exfoliatus F3-2 was identified as a novel 2,6-β-d-fructan 6-levanbiohydrolase (EC 3.2.1.64 ).

scholarly journals Anti-coagulant Activity of Isolated and Partially Characterized Proteoglycans and Glycosaminoglycans from African Night Crawler (Eudrilus eugeniae Kinberg)

KIMIKA ◽  
2015 ◽  
Vol 26 (2) ◽  
pp. 31-38
Author(s):  
Mia Clare Marie L. Bercansil ◽  
Miko Lorenzo J. Belgado
Keyword(s):  
Hyaluronic Acid ◽  
Infrared Spectroscopy ◽  
Enzymatic Hydrolysis ◽  
Gel Filtration ◽  
Acetate Buffer ◽  
Eudrilus Eugeniae ◽  
Gel Filtration Chromatography ◽  
Molecular Weights ◽  
Coagulant Activity ◽  
Hydrolysis Of

Proteoglycans and glycosaminoglycans were isolated from African night crawler (Eudrilus eugeniae Kinberg) and partially characterized proteoglycans (3.04 % of lyophilized worm) were liberated from the defatted and depurinated worm samples by dissociative method using 4M urea in acetate buffer. Glycosaminoglycans (12.47% of proteoglycan extract) were extracted using enzymatic hydrolysis of the proteoglycan extract with papain. Gel filtration chromatography using Sepharose CL-4B was used to purify and estimate the molecular weights of the proteoglycan and glycosaminoglycan fractions. Three proteoglycan fractions PGF1, PGF2 and PGF3 with estimated molecular weigths 860 kDa, 181 kDa and 3 kDa, respectively were identified as monitored by the Bradford and modified carbazole assay. Two glycosaminoglycan fractions - GF1 (MW = 860 kDa) and GF2 (MW=140 kDa) were identified using the modified carbazole assay. Infrared spectroscopy of the GF1 and GF2 showed the possible identities of the fractions. GF1 may be a hyaluronic acid and GF2 is possibly chondroitin. Anti-coagulant assay for the extracts and fractions revealed that the glycosaminoglycan isolate has anti-coagulant activity but not the GF1 and GF2 fractions individually.

scholarly journals Characterization of Melanoidins and Color Development in Dulce de Leche, a Confectionary Dairy Product With High Sucrose Content: Evaluation of pH Effect, an Essential Manufacturing Process Parameter

2021 ◽  
Vol 8 ◽  
Author(s):  
Analía Rodríguez ◽  
Patricia Lema ◽  
María Inés Bessio ◽  
Guillermo Moyna ◽  
Cristina Olivaro ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Ph Effect ◽  
Dairy Product ◽  
Gel Filtration ◽  
Significant Degree ◽  
Product Analysis ◽  
Molecular Weights ◽  
Ph Values ◽  
Initial Ph

The effect on color of the initial pH employed in dulce de leche (DL) production was evaluated through physicochemical and spectroscopical characterization of the melanoidins formed in the process. Melanoidins originated at pH values of 6.5, 7.0, and 7.5, and they were released by the enzymatic hydrolysis of the protein backbone and purified by gel filtration. They showed a significant degree of polydispersity, in general, with molecular weights (MWs) below 1,800 Da. DL produced at a higher pH released melanoidins with higher average MW after the enzymatic hydrolysis. They also presented darker colors (dE*ab, C*), more closely resembling those typical of the commercial product. Analysis of the fractions isolated by gel filtration using HPLC-DAD and multinuclear NMR showed an heterogeneous and complex composition. Even though structurally related, the 1H NMR spectra of melanoidins showed a higher degree of aromaticity at higher pH values. In conclusion, the pH employed in DL production affects the amount and structure of the colored products originated by MR reactions, and thus the color of the final product.

Two types of xylanases of alkalophilic Bacillus sp. No. C-125

1985 ◽  
Vol 31 (6) ◽  
pp. 538-542 ◽  
Author(s):  
H. Honda ◽  
T. Kudo ◽  
Y. Ikura ◽  
K. Horikoshi
Keyword(s):  
Ammonium Sulfate ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Bacillus Sp ◽  
Ammonium Sulfate Precipitation ◽  
Molecular Weights ◽  
Protein Molecules ◽  
Activity Curve ◽  
Alkalophilic Bacillus ◽  
Hydrolysis Of

One alkalophilic Bacillus sp. strain C-125 (FERM No. 7344) was isolated from soil. From this organism, two types of xylanases, designated xylanase A and xylanase N, were purified by an ammonium sulfate precipitation followed by Biogel P-30 gel filtration, DEAE-cellulose chromatography, and Sephadex G-75 gel filtration. The molecular weights of xylanase A and N were estimated as 43 000 and 16 000, respectively. Immunological experiments indicated that xylanase A and xylanase N were entirely different protein molecules. Xylanase N was most active at pH 6.0–7.0, but xylanase A had a very broad pH activity curve (pH 6–10) and was still active even at pH 12.0. The maximum hydrolysis of xylan by the enzymes was about 25%. Both enzymes split xylan and yielded xylobiose and higher oligosaccharides but could hydrolyze neither xylobiose nor xylotriose. Trans xylosidation activities were detected in both enzymes.

Solubilisierung, Anreicherung und Separierung zweier 17β-HSDAktivitäten nach Phospholipase-Behandlung / Microsome-Associated 17β-Hydroxysteroid Dehydrogenases of Human Placenta, I Solubilization, Enrichment and Separation of Two 17β-HSD-Activities after Phospholipase-Treatment

1975 ◽  
Vol 30 (1-2) ◽  
pp. 4-16b ◽  
Author(s):  
Kunhard Pollow ◽  
Wilfried Runge ◽  
Barbara Pollow
Keyword(s):  
Human Placenta ◽  
Gel Filtration ◽  
Hydroxysteroid Dehydrogenase ◽  
Phospholipase A ◽  
Membrane Phospholipids ◽  
Molecular Weights ◽  
Ammonium Sulphate Precipitation ◽  
Isoelectric Points ◽  
Hydrolysis Of ◽  
Estradiol 17Β

Abstract Treatment of human placenta microsomes with phospholipase A or D inhibits the 17β-hydroxysteroid dehydrogenase [17β-HSD] activity, parallel with the hydrolysis of membrane phospholipids. The 17β-HSD activity of phospholipase treated microsomes is reactivated by synthetic phospholipids. The distribution of 17β-HSD activity in subfractions of original microsomes and of phospholipase treated microsomes obtained by zonal centrifugation was studied. Solubilization of the microsomal 17β-HSD was achieved by phospholipase A treatment. Two 17β-HSD were solubilized from human placenta microsomes by phospholipase A treatment and were further purified by ammonium sulphate precipitation, gel filtration on BioGel A-0.5 m, DEAESephadex chromatography and by isoelectric focusing. The enzymes were purified 25.8 and 17.4 times. The isoelectric points and molecular weights of the two 17β-HSD were determined. Both enzymes are of a 17β-HSD type. One of the 17β-HSD, however, was sensitive to estradiol- 17β, the other to testosterone. The question of whether the two enzymes constitute a monomer and a dimer of the same 17β-HSD or are completely different enzymes, is discussed.

Naphthylamidases of Sarcina lutea

1971 ◽  
Vol 17 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Francis J. Behal ◽  
Rita T. Carter
Keyword(s):  
Divalent Cations ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Substrate Specificities ◽  
Molecular Weights ◽  
Hydrolysis Of

The naphthylamidase isozyme complement of Sarcina lutea was studied. Gel filtration yielded two fractions, Sephadex I and Sephadex II. Sephadex I contained one enzyme generally resembling leucineaminopeptidase. Sephadex II, upon ion exchange chromatography, yielded three isozymes, A, B, and C. These three were characterized with respect to molecular weight, substrate specificities, and effects of hydrogen ion concentration, EDTA, and divalent cation on reaction velocity. The molecular weights are 8.0 × 104, 8.2 × 104, and 9.0 × 104 respectively. Isozymes A and B are neutral naphthylamidases and preferentially catalyze the hydrolysis of alanine-β-naphthylamide (βNA), whereas isozyme C is a basic naphthylamidase and preferentially catalyzes the hydrolysis of lysine and arginine-βNA. The pH optima for the isozymes are 7.6, 7.6, and 6.7, respectively. All of the isozymes are sensitive to the effects of EDTA. Divalent cations activate the enzymes and reverse inhibition caused by EDTA.

scholarly journals Two benzaldehyde dehydrogenases in bacterium N.C.I.B. 8250. Distinguishing properties and regulation

1972 ◽  
Vol 130 (4) ◽  
pp. 927-935 ◽  
Author(s):  
A. Livingstone ◽  
C. A. Fewson ◽  
S. I. T. Kennedy ◽  
L. J. Zatman
Keyword(s):  
Alcohol Dehydrogenase ◽  
Benzyl Alcohol ◽  
Gel Filtration ◽  
Wild Type ◽  
Thermal Stabilities ◽  
Molecular Weights ◽  
Ph Values ◽  
Heat Stable ◽  
Benzaldehyde Dehydrogenase ◽  
Wild Type Bacterium

Evidence is presented for the existence in bacterium N.C.I.B. 8250 of two inducible NAD+-linked benzaldehyde dehydrogenases. They may be distinguished in crude extracts by their different thermal stabilities at high pH values, benzaldehyde dehydrogenase I being much more heat-stable than benzaldehyde dehydrogenase II. Only benzaldehyde dehydrogenase I is activated by K+ and certain other univalent cations. Gel-filtration experiments indicate that both enzymes have molecular weights of about 180000. Both enzymes are induced by growth on l-mandelate or phenylglyoxylate; only benzaldehyde dehydrogenase I is gratuitously induced by thiophenoxyacetate and only benzaldehyde dehydrogenase II is induced by benzyl alcohol, by benzaldehyde, and by a number of heterocyclic compounds which do not support growth. Mutants have been isolated that lack either benzaldehyde dehydrogenase II or benzyl alcohol dehydrogenase, or both of the enzymes. Results obtained in induction experiments with the wild-type bacterium N.C.I.B. 8250 and with the mutants show that benzaldehyde dehydrogenase II and benzyl alcohol dehydrogenase are co-ordinately regulated. Overall, the results suggest that benzaldehyde dehydrogenase I is associated with the metabolism of l-mandelate whereas benzaldehyde dehydrogenase II is associated with the metabolism of benzyl alcohol.

Comparative Study of Proactivators of the Fibrinolysin System in Three Mammalian Species

1969 ◽  
Vol 21 (03) ◽  
pp. 594-603 ◽  
Author(s):  
Y Takada ◽  
A Takada ◽  
J. L Ambrus
Keyword(s):  
Guinea Pig ◽  
Comparative Study ◽  
Human Plasma ◽  
Mammalian Species ◽  
Gel Filtration ◽  
Plasminogen Activators ◽  
The Other ◽  
Rabbit Plasma ◽  
Plate Test ◽  
Fibrin Plate

SummarySephadex gel filtration of human plasma gave results suggesting the presence of two proactivators of plasminogen, termed proactivators A and B.Activity resembling that of proactivator A was found in rabbit plasma, but not in guinea pig plasma.Plasminogen activators produced by the interaction of proactivator A of human plasma with streptokinase had no caseinolytic or TAMe esterolytic effect.Proactivator A can be separated in a form apparently free from plasminogen, as shown by the heated fibrin plate test and by immunological analysis. On the other hand, proactivator B concentrates prepared so far are contamined with plasminogen.Human proactivators appear to be far more susceptible to streptokinase than are rabbit proactivators.Inhibitors of the fibrinolysin system were observed in the plasmas of all 3 species. These inhibitors are not present in the euglobulin fraction of plasma. Sephadex fractionation of euglobulin fractions results in proactivator preparations that do not contain inhibitors.

Influence of Coagulation on the Activation of Plasminogen by Streptokinase and Urokinase

1979 ◽  
Vol 42 (03) ◽  
pp. 901-908 ◽  
Author(s):  
Akikazu Takada ◽  
Tetsumei Urano ◽  
Yumiko Takada
Keyword(s):  
Human Plasma ◽  
Fibrin Clot ◽  
Chromogenic Substrate ◽  
Hydrolysis Of

SummaryHuman plasma was mixed with Ca++ or thrombin, and urokinase (UK) or streptokinase (SK) and a chromogenic substrate (S-2251: H-D-Val-Leu-Lys-pNA) specific to plasmin. The hydrolysis of S-2251 was higher when clot was formed by the addition of Ca++ or thrombin than in the absence of clot. The hydrolysis of S-2251 by euglobulin in the presence of UK was also higher when clot was formed, thus, inhibitors may not be related to the better activation of plasminogen, in the presence of fibrin clot. It may be suggested that plasminogen was better activated by activators (UK and SK) in the clot than in its absence.

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